Runescape is a very good browser MMO it has free play and a subscription mode
that allows access to more quests content and skills.
Most mmorpgs that are any good have already updated their clients for the game. You just need to go to the site. And look on their forums and they should have how to download and operate on vista. Some good games are listed here: onmmorpg.
well theres stardoll
Wolfquest : your a wolf and u hunt try to survive an
The Sims 3 is a good website you can chat and meet new people, but the thing is that you have to download it. also buildabearville, you dont have to download it.many good websites are good
Meez.com, zwinkycuties.com, facebook.com, and myspace.com
Adventure Quest
check out this old school 2d mmo. http://www.crashdragon.com/MG/ML/index.html
http://www.freemmorpglist.com/ has 40 pages of them.
Find these on Nexon Mabinogi Vindictus
Luna online is pretty fun.
Some of the best free MMORPG games are NeverWinter, Planet Calypso, Dragon's Prophet, 4Story (Gates of Andaron), and 9Dragons. These are just a few of the highest rated free games.
Ruler of Zu Dragon's Call World of Dragons